Distillation and treatment of crude bituminous material.



H. W. ASH.

DISTILLATION AND TREATMENT OF CRUDE BITUMINOUS MATERIAL.

. APPLICATION FILED APR.17, 1902.

'MW it? Patented January 3, 1905.

PATENT TTTcn.

HORACE W. ASH, OF CAMBRIDGE,

WVARREN BROTHERS COMPANY,

MASSACHUSETTS, ASSIGNOR TO OF BOSTON, MASSACHUSETTS,

A CORPORATION OF WEST VIRGINIA.

DISTILLATION AND TREATMENT OF CRUDE BITUMINOUS MATERIAL.

SPECIFICATION forming part of Letters Patent No. 779,197., dated January 3, 1905.

Application filed April 1'7, 1902. Serial No. 103,346-

To all whom it may concern.-

Be it known that I, HORACE W. AsH, a citizen of the United States, and a resident of Cambridge, in the county of Middlesex and State of Massachusetts, have invented anew and useful Improvement in the Distillation and Treatment of Crude Bituminous Material, of which the following is a full, clear, and exact description.

My invention relates to the treatment of crude bituminous material to the end that there may be evolved therefrom a refined product especially adapted for use in themanufacture of bituminous pavements. By the variation, however, of certain details of my process, as will hereinafter appear, the product may be more especially suitable for roofing and other purposes. So far as the general principles of my invention are concerned the particular source or the precise composition or nature of the crude material is not of consequence, since these factors merely determine quantitive details of the process and have no substantial effect upon the final product.

My invention relates to the rapid distillation and the simultaneous or substantially simultaneous inspissation or thickening of the crude material, whereby the water and undesirable oils are drawn off and the composition of the remaining material so changed in character as regards its susceptibility to change of temperature, its elasticity, its toughness, &c., as to render it peculiarly valuable for the particular uses for which it is intended.

The distillation or ejection of the undesirable elements I accomplish by subjecting the crude material to a hot blast, preferably forced upward through the same, whereby the water and light oils are carried off as vapors. The inspissating or thickening of the material in the still I accomplish by causing such a blast to act as a carrier of finely-divided mattercarbon, for instance--which matter is deposited in the material subjected to the blast and alters the character of the same as desired. The products of combustion from a suitably fed and regulated furnace may constitute such a blast Without subsequent introduction of carbon, &c. Otherwise the carbon or other impurity may be injected into the blast at any point before the latter reaches the still. The nature of the blast is of course susceptible of variation within wide limits, although it may.

be somewhat governed in instances by the specific composition of the crude material and by other factors. Where the crude material already contains a large amount of carbon or similar impurity the amount of finely-divided matter to be supplied by the blast will be less than were the contrary the case. Again, the amount of such matter appearing in the final product will vary according to the uses for which the product is intended.

In order to render any particular crude bituminous material suitable for any special purpose, my process to subject that material for apredetermined time to a blast supplying the proper amount of matter to be deposited. Crude material from any given source is for the purposes of my invention substantially uniform in character, and therefore the amount of impurity and time of distillation required to prepare material from a certain source for any particular use has to be determined roughly but once. Such determinations I preferto make by experimentation as to time of blast and amount of impurity, the resulting product being tested as to its physical qualities in each instance by suitable apparatus. It is apparent, however, that the determinations can be based on chemical instead of physical tests. In conducting subsequent distillations of the same material the results previously obtained will serve as approximations, and it is only it is only necessary in carrying outnecessary to test at intervals the material in the still as its nears completion in order to secure a substance perfectly adapted for the intended use. The material having been sufliciently treated, I prefer to cool the same by subjecting it to a cool blast.

ered that in this way the contents of the still are not only much more rapidly cooled, but it is of auniform and better quality than when I have discovit is allowed to cool gradually from the exterior of the still to its center, as is now customary.

I will now describe the invention in conj unction with the drawing, where the figure is a viefiv in asomewhat conventional form of the sti Referring to the drawing, A represents an upright metal shell, preferably cylindrical in section, forming a distilling-chamber a, having an inlet a, by which the crude material is fed to it from a reservoir, an outlet 6& in its bottom a closed by a valve (5, through which the refined product is drawn, one or more gage-cocks a, and a thermometer a. It is represented upon a frame or legs a in a manner to provide room for tracks a beneath the outlet and for a car (not shown) adapted to receive the product or to hold barrels or hogsheads for receiving it,.whereby ease in handling the product is secured.

The still preferably has its bottom a round ed outwardly or downwardly. It also has the usual outlet (4 at its top, connecting with a condenser (0 which may be of the usual character. It further has asupply-pipe B, which enters its side near the top to about its center and then extends downward and opens in the bottom of the still below the diaphragm b. This pipe upon the outside of the still extends from a hot-air chamber B, in which is a blower for blowing hot air of any desired temperature and at any required pressure through the air-pipe into the still. The perforations of the diaphragm b may be of any desired size and they may be of any desired arrangement. Above the diaphragm Z) are the diaphragms 6 6 These are placed at convenient distances apart, extend across the still, and provide perforations which are preferably small,but may be of any size or arrangement. I have shown two diaphragms; but as many may be used as desired. Their purpose is to cause the bubbles, which tend to increase in size as the air rises through the distilling material, to be divided into smaller bubbles or globules in order to produce larger aerating surfaces from the quantity of air used and also for the purpose of reducing the speed with which the air passes through the distilling material and also tomore uniformly disseminate it throughout the mass as it is passing. This air acts as a vaporizer or liberating agency by means of which the distilling product is freed by volatilization from the oils, which it is necessary to distil off to produce a bituminous product of the desired consistency. This method of complete distillation is not only much quicker than the old method, as ordinarily it will require not more than seven hours for what has before taken over twenty to accomplish, but it may also be done at a temperature of about 300 Fahrenheit, where a temperature of 700 has before been used, and therefore not only is a material saving of time in distillation accomplished and the capacity ,of the still for producing a bituminous product so much increased, but' the cost of distillation is also more than correspondingly lessened, because of the saving in the amount of heat required and the duration of time it is used.

The air may be heated and forced through the air-supply pipe by any desired means. I

either soft coal or oil, or both. This furnace is represented as connected with the hot-air chamber B by a flue 6 through which the heat and all the products of combustion enter the hot-air chamber B. The air-forcing means in the chamber B provide an inducing-draft for the furnace and force all the products of combustion, as well as the heat, through the air-supply pipe into the still. Any lampblack, therefore, which is produced in the furnace is fed into the still.

The blower in the hot-air chamber (not shown) is provided with a shaft-pulley and is operated by a belt in the usual way.

When it is desired that the bituminous product shall contain lampblack, it may be produced in the furnace and hot-air chamber by imperfect combustion of the coal or preferably of oil therein, the combustion of the oil being sov regulated as to produce lampblack or carbon, which with the heated air is blown through the air-supply pipe into the still and there intimately mingled by means of the heated aeration with the heated distilling material. Where lampblack taken from other sources or other impalpable powder is used, it is fed into the air-supply pipe through a supply-hopper B through a suitable feeding-valve and is by the heated air conveyed to the still and by it intimately associated or mingled with the distilling product. The lampblack or impalpable powder is usually not introduced into the distilling product until near the end of its distillation.

The temperature of the heated air is of course dependent upon the fire. It is varied at will by the admission of cool air, which may be done by opening the furnace-door. It is thus possible to hasten the cooling of the product remaining in the still itself after distillation by forcing through the said product and the still cool or cold air rather than heated air, the fire in the furnace,of course, then being lessened or checked. From one to twenty per cent. of lampblack or other impalpable powder is used in providing the bituminous product resulting from the distillation with the desired stiffness. The physical and other properties of crude bituminous material are such as to render it substantially impossible to determine in advance all the conditions of distillation and to what extent impalpable powder may be introduced to stiffen it, and it is generally customary to continue the distillation until a product has been reached which will show suitable have represented a furnace B adapted to burn characteristics when subjected to a Bowen penetration-machine at about 7 8 Fahrenheit.

A bituminous product for paving purposes must have a suitable consistency, density, and disposition to harden at certain temperatures and to remain sufficiently hard within the ordinary range of atmospheric temperatures without becoming brittle on the one hand or soft on the other.

In use the still is filled to the desired extent with the crude tar or oil, and the hot air is then blown into the bottom of the still beneath it at about the temperature of 3100 Fahrenheit and about the pressure of five pounds to the square inch, and this causes the crude tar or oil to be heated, and thus to become more fluid and at the same time introduces into it an agitating and aerating influence which serves to combine with the gases of distillation at the same time that it serves to heat the mass throughout, the hot-air bubbles or globules gradually rising through the mass, permeating it, and escaping with the gas into the condenser. The hot-air-supply pipe is led down through the'center of the still to prevent conduction of heat from the pipe and also to retain such air reheating values as may arise from surrounding the pipe with the heated material. It also prevents the fluid contents of the still from flowing back from the still through the pipe in case the air-pressure is discontinued.

The shell of the still by my invention is not subjected to the intense heat of a furnace and cannot be burned out by a tendency to deposit coke upon the bottom, as is the case with ordinary stills. In other words, the still becomes practically indestructible, whereas with the present methods its plates are often burned out and the still destroyed.

Having thus fully described my invention, I

' claim and desire to secure by Letters Patent of the United States- 1. The method of distilling and inspissating crude bituminous material herein described, the same comprising the subjection of the said material in a still to a distilling heat and depositing in the distilling material an impal pable powder.

2. The method of distilling and inspissating crude bituminous material consisting in subjecting the same directly to a blast of air heated and charged with such finely-divided matter as is desired to be deposited therein.

3. The method of distilling and inspissating crude bituminous material consisting in subjecting the same to the passage of a hot blast of air and lampblack.

4. The method of distilling and inspissating crude bituminous material consisting in subjecting the same while at about the temperature 300 Fahrenheit to the passage of a blast of heated air and finely-divided matter until distillation is completed.

5. The method of distilling and inspissating crude bituminous material involving the subjection of the same to a blast loaded with finely-divided matter, which matter is thus forced into and deposited in the material.

6. The method of distilling and treating crude bituminous material consisting in subjecting the same directly to a heated blast until the product is of the proper grade and then cooling said mixture by subjecting the same directly to a cooling-blast.

HORACE W. ASH.

Witnesses:

F. F. RAYMOND, 2d, J. M. DOLAN. 

